Dual Phase Ferrite-Martensitic Steel Micro-Alloyed with V-Nb
For low-carbon V-Nb micro-alloyed steel, dual phase ferrite-martensitic microstructures were prepared with a variable martensite fraction, which ranged from Vm 20 to 88%. By measuring the temperature in the sample centre, the parameters of intercritical annealing and the relationship between Vm and...
Saved in:
Published in | Metalurgija Vol. 46; no. 1; pp. 15 - 20 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Croatian Metallurgical Society
01.01.2007
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | For low-carbon V-Nb micro-alloyed steel, dual phase ferrite-martensitic microstructures were prepared with a variable martensite fraction, which ranged from Vm 20 to 88%. By measuring the temperature in the sample centre, the parameters of intercritical annealing and the relationship between Vm and the intercritical annealing temperature 720 °C <= t <= 850 °C were determined. By analysing the microstructure, the strength and plastic properties of this dual phase steel, the preparation method of dual phase ferrite-martensitic steels was tested. Dual phase ferrite-martensitic microstructures at Vm above 53% formed continuous martensite areas. A change of the microstructure type as compared with the state with Vm < 53% resulted in a change of the increase of RpO2 and Rm. With growing Vm the strength properties increased and the plastic properties decreased. Fractures after uniaxial loading had a ductile pit morphology. On extraction carbon replicas, changes of precipitation of fine disperse precipitates were studied on the normalized state and the intercritically annealed state. |
---|---|
ISSN: | 0543-5846 1334-2576 |